Networked computing solutions allow for decoupling of storage assets from data consuming real and virtual computer devices. The storage can be remotely located from the physical devices and are not limited by the performance parameters of the calling real or virtual device(s). In order to achieve acceptable storage densities and costs, most networked storage systems rely on magnetic disk arrays, such as hard-disk drives (HDDs) as a primary storage medium. Because HDDs struggle to keep up with throughput requirements in many applications, storage systems augment arrays of these devices with double data rate (DDR)-backed caching, improving performance for frequently or recently accessed items. Unfortunately, it is prohibitively costly to achieve even moderate storage densities with DDR, limiting caching to a relatively small proportion of the total solution capacity. Thus, storage performance can be highly variable as some data is accessed in cache high speed, while many requests miss the cache and incurs slower disk and storage reading.
The proliferation of multi-level cell NAND flash memory (MLC NAND) as a higher density, high performance storage medium can improve storage system performance. MLC NAND integrated in to Solid State Disks (SSDs) arrays can provide input performance two orders of magnitude or greater than HDDs while achieving storage densities an order of magnitude higher than DDR magnetic storage. However, SSDs are still expensive compared to HDDs making a full caching system of only SSD storage systems very costly.